JPH0451408Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a magnetron, and in particular to a variable frequency mechanism of a magnetron.

[Conventional technology]

The space surrounded by the magnetron's anode cylinder and anode vane forms a resonant cavity (Figure 3a), and the tip of the vane is electrically coupled to the tip of an adjacent anode vane to create a capacitance there. The space on the anode cylinder side of the vane is magnetically coupled with the adjacent space and has an inductance. An equivalent representation of this is shown in FIG. 3b. In other words, the resonant frequency is determined by =2π1/√LC, so if the electrolysis generated near the anode vane of the magnetron or the magnetic field generated in the space on the anode cylinder side of the anode vane is changed, the capacitance or inductance will change and the resonant frequency will be changed. Can be varied. The "Kutsky cutter tuning method" to which this invention is applied is to vary the capacitance of the resonant circuit,
A groove is provided in the upper part or upper and lower part of the anode vane, and every other anode vane is connected to the groove part, and two annular strap rings are provided for mode separation. In the conventional technology, a metal tuner ring is inserted into the gap between two strap rings to change the capacitance and change the resonant frequency. (See Figure 4) [Problem that the invention attempts to solve] A metal tuner ring is used in the frequency variable mechanism of the conventional "Kutsky cutter tuning" method described above, and this is made up of two strut rings. inserted into the gap. When a magnetron operates, a high voltage is applied to the cathode and a high frequency electric field is generated at the anode. In this case, the high-frequency electric field generated at the anode is particularly strong as in the case of a magnetron with a large output, or the resonant cavity is small as in a magnetron with a high oscillation frequency, so the gap between the two strap rings is extremely narrow. This had the disadvantage that electrical discharge occurred between the metal tuner ring and strap ring used to vary the frequency, impairing the functionality of the magnetron.

[Means for solving problems]

The frequency variable mechanism of the "Kutsky cutter tuning" type according to the present invention has a tuner ring made of a dielectric material such as ceramic, or a tuner ring made of a metal cylinder coated with a dielectric material such as ceramic.

In other words, while a metal tuner ring is used in the frequency variable mechanism of the conventional "cut key cutter tuning" method described above, the present invention uses a dielectric tuner ring such as ceramic or a dielectric tuner ring instead of a metal tuner ring. It has an original content in that it uses a tuner ring made of a metal cylinder coated with a dielectric material such as ceramic.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a longitudinal sectional view of an embodiment of the present invention.
1 is an anode cylinder, 2 is an anode vane, 3 is a strap ring, and 4 is a tuner ring made of dielectric material such as ceramic. “Kutsky cutlet terchyuning”
This type of magnetron changes the resonant frequency by changing the capacitance of the resonant space by inserting a metal tuner ring between two strap rings. In the present invention, a dielectric tuner ring such as ceramic is used instead of the metal tuner ring, so that no discharge occurs between the strap ring and the dielectric tuner ring such as ceramic.

[Embodiment 2] FIG. 2 is a longitudinal sectional view of a frequency variable mechanism according to Embodiment 2 of the present invention. 5 is a metal cylinder 6 is a coating layer of dielectric material such as ceramic. In this embodiment, a metal cylinder is coated with a dielectric material such as ceramic, so that even if the base of the tuner ring is metal, an insulating layer of dielectric material such as ceramic prevents electrical discharge between the tuner ring and the strap ring. It has the advantage of being possible.

[Effect of idea]

As explained above, the present invention uses a tuner ring made of a dielectric material such as ceramic, or a tuner ring made of a metal cylinder coated with a dielectric material such as ceramic, in the frequency variable mechanism of a magnetron using the "cut-key cutter tuning" method. Therefore, even in a high-output magnetron or a magnetron with a high oscillation frequency, discharge between the tuner ring and the strap ring can be prevented, and a stable frequency variable mechanism can be provided.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention. FIG. 2 is a longitudinal sectional view of a frequency variable mechanism according to Example 2 of the present invention. Figures 3a and 3b show the magnetron's resonant cavity and its equivalent circuit. FIG. 4 is a longitudinal sectional view of an example of the conventional "cutting tool turning" method. DESCRIPTION OF SYMBOLS 1... Anode cylinder, 2... Anode vane, 3... Strap ring, 4... Tuner ring made of dielectric material such as ceramic, 5... Metal cylinder, 6... Coating layer of dielectric material such as ceramic, 7... ...Metal tuner ring.

Claims (1)

[Scope of utility model registration request] An anode cylinder, a plurality of anode vanes arranged radially on the inner surface of the anode cylinder, and two annular anode vanes installed in grooves provided at the top or upper and lower parts of the anode vane and connected to every other anode vane.
In a magnetron that has a main strap ring and a tuner ring for varying the frequency in the gap between the two straps, the tuner ring is made of a dielectric material such as ceramic, or a dielectric material such as metal and ceramic. A magnetron frequency variable mechanism characterized by a coated tuner ring.